Server device, non-transitory server device-readable storage medium, and game system

ABSTRACT

A server device connected to a first player terminal used by a first player and a second player terminal used by a second player to communicate with each other, including: a storage unit that stores player information in which each of items owned by players is associated with each of the players; a reception unit that receives, from the first player terminal, an exchange request to exchange a first item owned by the first player for a second item different from the first item, and receives, from the second player terminal after the exchange request, an acquisition request that the second player acquire the first item in an exchange source from the first player; a judging unit that judges whether or not the second player owns the second item based on the player information when the reception unit receives the acquisition request; and an item exchange processing unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority upon Japanese Patent ApplicationNo. 2012-147664 filed on Jun. 29, 2012, which is herein incorporated byreference.

BACKGROUND

1. Technical Field

This invention relates to a server device, a non-transitory serverdevice-readable storage medium, and a game system.

2. Related Art

A server device is known that is connected to a first player terminalused by a first player and a second player terminal used by a secondplayer so as to communicate with each other, and allows trading of itemsbetween the first player and the second player (for example, JapaneseLaid-Open Patent Publication No. 2003-126555).

The player had to follow a complex procedure when the foregoing trade ofitems was carried out, so that there were cases where the player tookthe time and effort to perform operations for the trade.

SUMMARY OF THE INVENTION

The present invention has been conceived in view of the above issue, andan object thereof is to allow the player to trade items without takingtime and effort.

An aspect of the invention to solve the above and other problems is aserver device that is connected to a first player terminal used by afirst player and a second player terminal used by a second player so asto communicate with each other, the server device including:

a storage unit that stores player information in which each of itemsowned by players is associated with each of the players;

a reception unit

-   -   that receives, from the first player terminal, an exchange        request to exchange a first item owned by the first player for a        second item different from the first item,    -   and receives, from the second player terminal after the exchange        request, an acquisition request that the second player acquire        the first item in an exchange source from the first player;

a judging unit that judges whether or not the second player owns thesecond item based on the player information when the reception unitreceives the acquisition request; and

an item exchange processing unit,

-   -   when the judging unit judges that the second player owns the        second item, that sets the second item owned by the second        player as a candidate item to be exchanged for the first item in        the exchange source,    -   and when the judging unit judges that the second player does not        own the second item, that transmits a game image for purchase to        the second player terminal, the game image being for allowing        the second player to purchase the second item.

Other features of this invention will become apparent from thedescription in the detailed description of the invention and theattached drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates an example of an overall configuration of a gamesystem 1 according to the present embodiment.

FIG. 2 is a block diagram of a functional configuration of a serverdevice 10 according to the present embodiment.

FIG. 3 is a block diagram of a functional configuration of a userterminal 20 according to the present embodiment.

FIG. 4 illustrates an example of a data structure of card information.

FIG. 5 illustrates an example of a data structure of item information.

FIG. 6 illustrates an example of a data structure of player information.

FIG. 7 illustrates an example of a data structure of owned cardinformation.

FIG. 8 illustrates an example of a data structure of owned iteminformation.

FIG. 9 illustrates an example of a data structure of trade information.

FIG. 10 is a flowchart describing an operation example of the gamesystem 1 according to the present embodiment.

FIG. 11 illustrates an example of an operating image for sellers wholist an item.

FIG. 12 illustrates an example of an operating image for bidders who bidfor a listing item.

FIG. 13 illustrates an example of an operating image for purchasing aninsufficient item.

FIG. 14 is a flowchart describing another operation example of the gamesystem 1 according to the present embodiment.

FIG. 15 illustrates an example of an operating image for purchasing aninsufficient item.

DETAILED DESCRIPTION OF THE INVENTION

With the detailed description of the present invention and theaccompanied drawings, at least the following matters will be apparent.

A server device that is connected to a first player terminal used by afirst player and a second player terminal used by a second player so asto communicate with each other, the server device including:

a storage unit that stores player information in which each of itemsowned by players is associated with each of the players;

a reception unit

-   -   that receives, from the first player terminal, an exchange        request to exchange a first item owned by the first player for a        second item different from the first item,    -   and receives, from the second player terminal after the exchange        request, an acquisition request that the second player acquire        the first item in an exchange source from the first player;

a judging unit that judges whether or not the second player owns thesecond item based on the player information when the reception unitreceives the acquisition request; and

an item exchange processing unit,

-   -   when the judging unit judges that the second player owns the        second item, that sets the second item owned by the second        player as a candidate item to be exchanged for the first item in        the exchange source,    -   and when the judging unit judges that the second player does not        own the second item, that transmits a game image for purchase to        the second player terminal, the game image being for allowing        the second player to purchase the second item.

According to such server device, when there is a shortage of seconditems to be traded, a game image for purchase for allowing the player topurchase the second item can be displayed on the player terminalimmediately. Therefore, the player is allowed to trade items withouttaking time and effort.

In such a server device, it is acceptable that

in the player information, the number of items owned by each of playersis associated with each of the players,

the reception unit

-   -   receives, from the first player terminal, an exchange request to        exchange M number of the first items for N number of the second        items, M being a positive integer, N being a positive integer,        and    -   receives, from the second player terminal after the exchange        request, an acquisition request that the second player acquire M        number of the first items from the first player,

the judging unit judges whether or not the number of the second itemsowned by the second player is more than the number N of the second itemsto be exchanged based on the player information, and

when the judging unit judges that the number of the second items ownedby the second player is less than the number N of the second items to beexchanged, the item exchange processing unit transmits a game image forpurchase to the second player terminal, the game image being forallowing the second player to purchase the number of the second itemsrequired to be added to equal N.

According to such server device, when the number of second items to betraded is insufficient, a game image for purchase for allowing theplayer to purchase the number of second items required to be added canbe displayed on the player terminal immediately. Therefore, the playeris allowed to trade items without taking time and effort.

In such a server device, it is acceptable that

the server device is connected to a third player terminal used by athird player who is different from the first player and the secondplayer so as to communicate with each other,

the reception unit

-   -   receives, from the second player terminal, an acquisition        request to acquire M number of the first items by accepting to        exchange N number of the second items owned by the second        player, and    -   receives, from the third player terminal after the acquisition        request from the second player terminal, an acquisition request        that the third player acquire M number of the first items from        the first player,

when the reception unit receives the acquisition request transmittedfrom the third player terminal, the judging unit judges whether or notthe number of the second items owned by the third player is more thanthe number N of the second items that the second player has accepted toexchange, based on the player information, and

when the judging unit judges that the number of the second items ownedby the third player is less than the number N of the second items thatthe second player has accepted to exchange, the item exchange processingunit transmits a game image for purchase to the third player terminal,the game image being for allowing the third player to purchase thenumber of the second items required to be added to be equal to or morethan N.

According to such server device, when the number of second items ownedby the third player is less than the number N of the second items thatthe second player has accepted to exchange, the third player needs thesecond items the number of which becomes more than the number thereofowned by the second player, and therefore a game image for purchase forallowing the player to purchase the number of second items required tobe added to be equal to or more than N can be displayed on the playerterminal immediately. This makes it possible to allow the third playerto trade items without taking time and effort.

In such a server device, it is acceptable that

the server device is connected to a third player terminal used by athird player who is different from the first player and the secondplayer so as to communicate with each other,

the reception unit

-   -   receives, from the second player terminal, an acquisition        request to acquire M number of the first items by accepting to        exchange N number of the second items owned by the second        player, and    -   receives, from the third player terminal after the acquisition        request from the second player terminal, an acquisition request        that the third player acquire N number of the second items from        the second player,

when the reception unit receives the acquisition request transmittedfrom the third player terminal, the judging unit judges whether or notthe number of the first items owned by the third player is more than thenumber M of the first items in the exchange source, based on the playerinformation, and

when the judging unit judges that the number of the first items owned bythe third player is less than the number M of the first items in theexchange source, the item exchange processing unit transmits a gameimage for purchase to the third player terminal, the game image beingfor allowing the third player to purchase the number of the first itemsrequired to be added to be equal to or more than M.

According to such server device, when the number of first items owned bythe third player is less than the number M of the first items in theexchange source, the third player needs the first items the number ofwhich becomes more than the number thereof entered by the first player,and therefore a game image for purchase for allowing the player topurchase the number of first items required to be added to be equal toor more than M can be displayed on the player terminal immediately. Thismakes it possible to allow the third player to trade items withouttaking time and effort.

Present Embodiment <Configuration of Game System 1>

FIG. 1 illustrates an example of an overall configuration of a gamesystem 1 according to the present embodiment. The game system 1 providesvarious types of services related to games to a player over a network 2(for example, the Internet and the like). The game system 1 includes aserver device 10 and a plurality of player terminals 20.

<Configuration of Server Device 10>

FIG. 2 is a block diagram of a functional configuration of a serverdevice 10 according to the present embodiment. The server device 10 isan information processing device (for example, a workstation, a personalcomputer, and the like) used by a person such as a system administratorwhen managing and controlling the game service. When the server device10 receives various commands (requests) from the player terminal 20, theserver device 10 is able to distribute a game program that is operableon the player terminal 20, web pages generated by a mark-up language(HTML and the like) suited to the standards of the player terminal 20,and the like. The server device 10 includes a control unit 11, a datastorage unit 12, an input unit 13, a display unit 14, and acommunication unit 15.

The control unit 11 is a unit that transfers data among the units andcontrols the entire server device 10, and is realized by a centralprocessing unit (CPU) executing a program stored in a certain memory.The control unit 11 according to the present embodiment includes areception unit 111, a judging unit 112, an item exchange processing unit113, and an image generation unit 114.

The reception unit 111 has a function to perform a process for receivingvarious operational commands (requests) from the player through theplayer terminal 20 over the network 2. The judging unit 112 has afunction to perform a process for judging whether or not tradeconditions for exchanging an item on an item exchange market describedbelow are satisfied (whether or not the trade is completed). The itemexchange processing unit 113 has a function to perform various processesrelated to an item exchange based on the judgment result produced by thejudging unit 112. The image generation unit 114 has a function toperform a process for generating various images (for example, Web pageslinked to image data related to a game) to be displayed on the playerterminal 20.

The data storage unit 12 has a read only memory (ROM) that is aread-only storage region in which system programs are stored, and arandom access memory (RAM) that is a rewritable storage region which isused as a work area for computing processes performed by the controlunit 11. The data storage unit 12 is realized, for example, by anon-volatile storage device such as a flash memory or a hard disk andthe like. The data storage unit 12 according to the present embodimentstores card information, player information, and item information: thecard information is information related to a game card used in a game;the player information is information related to the player; and theitem information is information related to the item used in a game. Theitem gives a player advantages in game progress. The item is, forexample, a tool, an ability and the like which can be used in a game.These pieces of information will be described later in detail.

The input unit 13 is a unit with which a system administrator, etc.input various types of data (card information, item information and thelike), and is realized, for example, by a keyboard, a mouse, and thelike.

The display unit 14 is a unit which displays operating screens for thesystem administrator according to commands from the control unit 11, andis realized, for example, by a liquid crystal display (LCD) and thelike.

The communication unit 15 is a unit for performing communication withthe player terminals 20, and has a function as a reception unit forreceiving signals and various data transmitted from the player terminals20, and a function as a transmission unit for transmitting the signalsand various data to the player terminals 20 in accordance with commandsfrom the control unit 11. The communication unit 15 is realized, forexample, by a network interface card (NIC) and the like.

<Configuration of Player Terminal 20>

FIG. 3 is a block diagram of a functional configuration of a playerterminal 20. The player terminal 20 according to the present embodimentis an information processing device (for example, a mobile telephoneterminal, a smartphone, and the like) used by a player when playing agame. The player terminal 20 is able to send a distribution request forvarious types of information (e.g., a game program and web pages)related to the game to the server device 10. Since the player terminal20 also has a web browser function for allowing players to view webpages, the web pages (e.g., game play images) distributed from theserver device 10 can be displayed on screens. The player terminal 20includes a terminal control unit 21, a terminal storage unit 22, aterminal input unit 23, a terminal display unit 24, and a terminalcommunication unit 25.

The terminal control unit 21 is a unit that transfers data among theunits and controls the entire player terminal 20. The terminal controlunit 21 is realized by a central processing unit (CPU) executing aprogram stored in a certain memory. The terminal storage unit 22 isconnected to the terminal control unit 21 through a bus. In accordancewith commands from the terminal control unit 21, the data stored in theterminal storage unit 22 is looked up, read, and rewritten. The terminalstorage unit 22 is realized, for example, by a flash memory or a harddisk and the like. The terminal input unit 23 is a unit with which theplayer performs various operations (game operations and the like), andis realized, for example, by an operating button, a touch screen or thelike. The terminal display unit. 24 is a unit for displaying a gamescreen (game image, operating image, and the like) according to commandsfrom the terminal control unit 21, and is realized, for example, by aliquid crystal display (LCD) and the like. The terminal communicationunit 25 is a unit for sending and receiving various information to/fromthe server device 10 over the network 2, and is realized, for example,by a network interface card (NIC) and the like.

<Data Structure>

FIG. 4 illustrates an example of a data structure of card informationstored in the data storage unit 12. The card information includes items(fields) such as a card ID, a character name, the level of thecharacter, attack power, defense power, and hit point. The card ID isidentification information for identifying a game card. The charactername is information indicative of display names of the character. Thelevel of the character, the attack power, the defense power, and the hitpoint are parameters indicating a skill value set for the character.

FIG. 5 illustrates an example of a data structure of item informationstored in the data storage unit 12. The item information includes itemssuch as an item ID, an item name, and the price of the item. The item IDis identification information for identifying an item. The item name isinformation indicative of display names of the item. The price of theitem is information indicative of a value of the item with virtualcurrency.

FIG. 6 illustrates an example of a data structure of player informationstored in the data storage unit 12. The player information includesitems such as a player ID, virtual currency, owned card information,owned item information, and trade information. The player ID isidentification information for identifying a player. The virtualcurrency is information indicative of the amount of virtual currencyowned by the player. The virtual currency is updated when the playeracquires and spends virtual currency (when the player purchases anitem). The owned card information is information indicative of a gamecard owned by the player (hereinafter referred to as an owned card). Theowned item information is information indicative of an item owned by theplayer (hereinafter referred to as an owned item). The trade informationis information related to the trade that the player has placed on themarket for exchanging an item.

FIG. 7 illustrates an example of a data structure of owned cardinformation included in the player information. The owned cardinformation includes items such as an owned card ID, the level of theowned card, attack power, defense power, hit point, and acquisitiondates and times. The owned card ID is identification information foridentifying the owned card. The level of the owned card, the attackpower, the defense power, and the hit point are parameters indicating askill value set for the character associated with the owned card. Thevarious parameters are updated in accordance with the result of thebattle game and the like. The acquisition dates and times areinformation indicative of the dates and times when the player acquiredthe owned card.

FIG. 8 illustrates an example of a data structure of owned iteminformation included in the player information. The owned iteminformation includes items such as an owned item ID, and the number ofowned items. The owned item ID is identification information foridentifying an owned item. The number of owned items is informationindicative of the number of owned items owned by him/herself.

FIG. 9 illustrates an example of a data structure of trade informationincluded in the player information. The trade information includes itemssuch as a trade ID, a listing item ID, the number of listings, a desireditem ID, and a desired number. The trade ID is identificationinformation for identifying the trade that the player has placed on themarket. The listing item ID is an item ID associated with the item theplayer has listed in the trade (hereinafter referred to as a listingitem). The number of listings is information indicative of the number oflisting items. The desired item ID is an item ID associated with theitem desired by the player in the trade (hereinafter referred to as adesired item). The desired number is information indicative of thenumber of the desired items.

<Game Outline>

An outline of the game provided by the game system 1 according to thepresent embodiment is described below. The game system 1 provides abattle game that is played using a game card (a virtual card used in avirtual space in the game) as one example of the game content, and anitem exchange market for trading items available in the battle game.

(Battle Game)

In the game system 1 according to the present embodiment, the player canown a plurality of game cards each associated with a game character. Theplayer can play a battle game by using a game card (character) selectedfrom among a plurality of game cards that the player owns. The controlunit 11 selects an enemy character that participated in the battle withthe character associated with the game card selected by the player, anddetermines the outcome of the battle game between the characters basedon various parameters (attack power, defense power, hit point and thelike) set for each character.

The player can use an item in the battle game. For example, the playeruses an item having a hit point recovery function, so that the controlunit 11 is able to recover the hit point parameter set for thecharacter.

Also, the player can purchase a desired item in the virtual currency,and acquire a desired item using the following item exchange market.

(Item Exchange Market)

In the game system 1 according to the present embodiment, the player canown a plurality of items available in the game. The player can place atrade for exchanging an item owned by him/herself for an item owned bythe other player, by using an item exchange market. The trade of theitem exchange is placed by the auction system. When the trade iscompleted, the player can acquire the item owned by the other playerinstead of giving the item owned by him/herself to the other player.

An example of operations when using the item exchange market will beexplained below in detail.

<An Example of Operations of Game System 1>

FIG. 10 is a flowchart describing an operation example of the gamesystem 1 according to the present embodiment. Here, a player terminal 20used by a player A (first player) is described as a player terminal A,and a player terminal 20 used by a player B (second player) is describedas a player terminal B.

First, in the player terminal A, when the terminal control unit 21receives a manipulated input performed by the player A (seller) from aterminal input unit 23, a listing request to list an item on the itemexchange market is transmitted to the server device 10 through theterminal communication unit 25 (S101).

Next, in the server device 10, when the reception unit 111 receives thelisting request which has been transmitted from the player terminal A,the image generation unit 114 generates an operating image (game image)for sellers who list an item (S102). The operating image is transmittedto the player terminal A that has issued the request through thecommunication unit 15.

Next, the player terminal A causes the terminal display unit 24 todisplay the operating image for sellers which has been transmitted fromthe server device 10 (S103). FIG. 11 illustrates an example of anoperating image 50 for sellers displayed on the terminal display unit24. The player A selects a desired listing item from among selectionitems in a pull-down menu by operating a menu button 51, and selects thenumber of the desired listing items from among selection items in apull-down menu by operating a menu button 52. Categories and the numberof the listing items included in the selection items are extracted basedon the owned item information (see FIG. 8) stored in the storage unit12. Similarly, the player A selects a desired item and the numberthereof to be exchanged by operating menu buttons 53 and 54. Then, afterthe listing item and desired item are confirmed, the player A selects alisting button 55. As shown in FIG. 11, in the present embodiment,“three” “item A”s are selected as the listing items, and “three” “itemX”s are selected as the desired items by the operation of the player A.

Referring back to FIG. 10, when the listing item and the number thereofin an exchange source, and the desired item and the number thereof to beexchanged are entered by the player A with the manipulated input in thisway, such operational information (exchange request to exchange thelisting item owned by the player A for the desired item) is transmittedfrom the player terminal A to the server device 10 (S104). Then, thecontrol unit 11 of the server device 10 receives the operationalinformation (exchange request) transmitted from the player terminal Athrough the reception unit 111, and updates trade information (see FIG.9) stored in the storage unit 12 based on the operational information(exchange request).

In this way, the trade entered by the player A (the exchange trade fromthe listing item to the desired item) is placed on the item exchangemarket.

In the player terminal B, when the terminal control unit 21 receives amanipulated input performed by the player B (bidder) from the terminalinput unit 23, a bid request to bid for the listing item placed on theitem exchange market is transmitted to the server device 10 through theterminal communication unit 25 (S105).

Then, in the server device 10, when the reception unit 111 receives thebid request transmitted from the player terminal B, the image generationunit 114 generates an operating image (game image) forbidders who bidfor the listing item (S106). The operating image is transmitted to theplayer terminal B that has issued the request through the communicationunit 15.

Next, the player terminal B causes the terminal display unit 24 todisplay the operating image for bidders which has been transmitted fromthe server device 10 (S107). FIG. 12 illustrates an example of anoperating image 60 for bidders, which is displayed on the terminaldisplay unit 24. In the operating image 60 for bidders, a list of thelisting items distinguished at each trading item is displayed. Thetrading item is extracted based on the trade information (see FIG. 9)stored in the storage unit 12. The player B selects an item that theplayer B accepts to exchange, from among a plurality of trading itemsincluded in the list of the listing items. As shown in FIG. 12, in orderto respond to the trade entered by the player A (see FIG. 11), that is,the trade for exchanging (three) “item A”s that are listing items for(three) “item X”s that are desired items, it is assumed that the (three)“item X”s are selected by the operation of the player B. With thisselection, the player B has bid for the (three) “item A”s that theplayer B would like to acquire.

Referring back to FIG. 10, when the “item X” is selected by theoperation of the player B in this way, such operational information(acquisition request that the player B acquire the listing item in theexchange source from the player A) is transmitted from the playerterminal B to the server device 10 (S108).

Next, in the server device 10, when the reception unit 111 receives theoperational information (acquisition request) transmitted from theplayer terminal B, the judging unit 112 performs a judgment process forjudging whether or not the exchange trade of the item selected by theplayer B is completed (S109). The judging unit 112 refers to the owneditem information (see FIG. 8) stored in the storage unit 12 to judgewhether or not the player B owns the desired item to be exchanged. Inthe present embodiment, since the player B has bid for the (three) “itemA”s listed by the player A (see FIG. 12), the judging unit 112 refers tothe owned item information (see FIG. 8) to judge whether or not thenumber of “item X”s owned by the player B is equal to or more than“three”.

Next, in the server device 10, based on the result judged by the judgingunit 112, the item exchange processing unit 113 performs variousprocesses related to the item exchange (S110).

In the present embodiment, when the judging unit 112 judges that theplayer B owns the (three) “item X”s that are desired items of the playerA, the item exchange processing unit 113 set the (three) “item X”s ownedby the player B as candidate items to be exchanged for the (three) “itemA”s in the exchange source. Then, if there is no bid from other players,and a predetermined period (for example, one hour) has past, the (three)“item A”s listed by the player A are exchanged for the (three) “item X”sowned by the player B, and the owned item information (see FIG. 8)stored in the storage unit 12 is updated.

On the other hand, when the judging unit 112 judges that the player Bdoes not own (three) “item X”s that are desired items of the player A,the item exchange processing unit 113 causes the image generation unit114 to generate an operating image for purchase for allowing the playerB to purchase the insufficient “item X” (S111). The operating image istransmitted to the player terminal B that has issued the request throughthe communication unit 15.

Note that, the image generation unit 114 can be made to generate theoperating image for purchase only when the insufficient “item X” is anitem the player B can purchase. Also, when the “item X” is an item thatthe player B can not purchase, the game image including an indicationthat “the item is insufficient” may be generated.

In this way, when the item to be traded is insufficient (or the numberof items is insufficient), it is possible to display the operating imagefor purchase for allowing the player to purchase the insufficient item(or operating image for purchase for allowing the player to purchase thenumber of items required to be added) on the player terminal 20immediately. This makes it possible for the player to trade the itemwithout taking time and effort.

Next, the player terminal B causes the terminal display unit 24 todisplay the operating image for purchase which has been transmitted fromthe server device 10 (S112). FIG. 13 illustrates an example of anoperating image 70 for purchase displayed on the terminal display unit24. In the operating image 70 for purchase, the number of insufficientitems is displayed from the beginning without causing the player tooperate the menu button and select a purchase quantity of theinsufficient items. In the present embodiment, for example, when thenumber of “item X”s required to be added is “three” (when the playerowns none of the “item X”s), “3” is displayed on a purchase quantityfield 71 in the operating image 70 for purchase, as shown in FIG. 13.Moreover, for example, when it is judged that the number of “item X”srequired to be added is “two” as a result of the judgment produced bythe judging unit 112 (when “one” “item X” is owned), “2” is displayed onthe purchase quantity field 71.

This makes it possible for the player B to purchase the insufficient“item X” without taking time and effort only by selecting a purchasebutton 72 in the operating image 70 for purchase, and complete the tradefor exchanging the (three) “item A”s that are the listing items of theplayer A for the (three) “item X”s that have become owned items ofhim/herself.

<Other Example of Operations of Game System 1>

FIG. 14 is a flowchart describing the other example of operations of thegame system 1 according to the present embodiment. Here, the playerterminal 20 used by a player A (first player) is described as a playerterminal A, the player terminal 20 used by a player B (second player) isdescribed as a player terminal B, and the player terminal 20 used by aplayer C (third player) is described as a player terminal C.

The following describes operation examples of the game system 1 in thecase where the reception unit 111 in the server device 10 receives alisting request on the item exchange market from the player terminal Abased on a manipulated input performed by the player A (seller), thereception unit 111 then receives a bid request for the listing itemplaced on the item exchange market by the player A, from the playerterminal B based on a manipulated input performed by the player B(bidder), and then the reception unit 111 further receives a bid requestfrom the player terminal C based on a manipulated input performed by theplayer C (bidder).

First, when the player terminal C transmits, to the server device 10, abid request for the listing item placed on the item exchange marketbased on the manipulated input performed by the player C (bidder)(S201), the server device 10 responds to the bid request, causes theimage generation unit 114 to generate an operating image for bidders(S202), and transmits the operating image to the player terminal C thathas issued the request.

Next, the player terminal C causes the terminal display unit 24 todisplay an operating image for bidders (see FIG. 12) which has beentransmitted from the server device 10 (S203). The player C selects anitem that the player C accepts to exchange, from among a plurality oftrading items included in a list of the listing items. In the presentembodiment, for example, the player C can select (three) “item X”s inthe operating image 60 for bidders in order to acquire (three) “item A”slisted by the player A (see FIG. 12). This selection results in a bidfrom the player C for the (three) “item A”s owned by the player A. Insuch a case, the player B and the player C are to compete for acquiringthe “item A”s owned by the player A. Additionally, for example, theplayer C can also select (three) “item A”s in the operating image 60 forbidders in order to acquire the (three) “item X”s that the player B hasaccepted to exchange when bidding. This selection results in a bid fromthe player C for the (three) “item X”s owned by the player B. In such acase, the player A and the player C are to compete for acquiring the“item X”s owned by the player B.

Referring back to FIG. 14, when the item is selected by the operation ofthe player C in this way, such operational information (acquisitionrequest that the player C acquire the “item A” from the player A, oracquisition request that the player C acquire the “item X” from theplayer B) is transmitted from the player terminal C to the server device10 (S204).

Next, in the server device 10, when the reception unit 111 receives theoperational information (acquisition request) which has been transmittedfrom the player terminal C, the judging unit 112 executes a judgmentprocess for judging whether or not the trade for exchanging the itemselected by the player C is completed (S205). In the present embodiment,the player B and the player C compete against each other for the (three)“item A”s, or the player A and the player C compete against each otherfor the (three) “item X”s. Therefore, the following judgment process isexecuted by the judging unit 112.

First, when the reception unit 111 receives an acquisition request thatthe player C acquire the “item A” from the player A, the judging unit112 judges whether or not the number of “item X”s owned by the player Cis more than “three”, which is the number of “item X”s the player B hasbid for, by referring to the owned item information (see FIG. 8) storedin the storage unit 12. That is because the player C is not able to makea successful bid for the “item A” of the player A if the player C doesnot offer the “item X”s, to the player A, the number of which is morethan the number of the “item X”s the player B has already bid for.

On the other hand, when the reception unit 111 receives an acquisitionrequest that the player C acquire the “item X” from player B, thejudging unit 112 judges whether or not the number of “item A”s owned bythe player C is more than “three” that is the number of “item A”s listedby the player A, by referring to the owned item information (see FIG. 8)stored in the storage unit 12. That is because the player C is not ableto make a successful bid for the “item X” of the player B if the playerC does not offer the “item A”s, to the player B, the number of which ismore than the number of “item A”s listed by the player A.

Next, in the server device 10, based on the judgment result performed bythe judging unit 112, the item exchange processing unit 113 performsvarious processes related to the item exchange (S206).

First, in the case that the reception unit 111 receives an acquisitionrequest for the “item A” requested by the player C, when the judgingunit 112 judges that the player C owns “item X”s the number of which ismore than “three”, which is the number of “item X”s the player B has bidfor, the item exchange processing unit 113 sets the “item X”s (thenumber of which is more than three) owned by the player C as candidateitems to be exchanged for the (three) “item A”s in the exchange source.Then, if there is no bid from other players, and a predetermined period(for example, one hour) has past, the player C acquires the (three)“item A”s. Thus, the (three) “item A”s listed by the player A areexchanged for the “item X”s (the number of which is more than three)owned by the player C, and the owned item information (see FIG. 8)stored in the storage unit 12 is updated. Note that, when theabove-mentioned judgment is made by the judging unit 112, or the numberof “item X”s that the player C has bid for is equal to or more than apredetermined quantity (for example, equal to or more than 10), the itemexchange processing unit 113 may cause the player C to acquire the(three) “item A”s in the exchange source immediately.

On the other hand, when the judging unit 112 judges that the player Cowns “item X”s the number of which is less than “three”, which is thenumber of “item X”s the player B has bid for, the item exchangeprocessing unit 113 causes the image generation unit 114 to generate anoperating image for purchase for allowing the player C to purchase thenumber of “item X”s required to be added to be equal to or more than“three” (S207). The operating image is transmitted to the playerterminal C that has issued the request through the communication unit15.

In this way, the player C can bid for the trade for exchanging the “itemX”s, the number of which is more than the number of “item X”s the playerB has already bid for, for the “item A”s listed by the player A withouttaking time and effort.

Compared to this, in the case that the reception unit 111 receives anacquisition request for “item X” requested by the player C, when thejudging unit 112 judges that the player C owns “item A”s the number ofwhich is more than “three”, which is the number of “item A”s listed bythe player A, the item exchange processing unit 113 sets the “item A”s(the number of which is more than three) owned by the player C ascandidate items to be exchanged for the (three) “item X”s in theexchange source. Then, if there is no bid from other players, and apredetermined period (for example, one hour) has past, the player Cacquires the (three) “item X”s. Thus, the (three) “item X”s of theplayer B are exchanged for the “item A”s (the number of which is morethan three) of the player C, and the owned item information (see FIG. 8)stored in the storage unit 12 is updated.

On the other hand, when the judging unit 112 judges that the player Cowns “item A”s the number of which is less than “three”, which is thenumber of “item A”s listed by the player A, the item exchange processingunit 113 causes the image generation unit 114 to generate an operatingimage for purchase for allowing the player C to purchase the number of“item A”s required to be added to be equal to or more than “three”(S207). The operating image is transmitted to the player terminal C thathas issued the request through the communication unit 15.

In this way, the player C can bid for the trade for exchanging the “itemA”s, the number of which is more than the number thereof listed by theplayer A, for the “item X”s of the player B without taking time andeffort.

Next, the player terminal C causes the terminal display unit 24 todisplay the operating image for purchase which has been transmitted fromthe server device 10 (S208).

First, when the player C would like to acquire the “item A” of theplayer A, in a operating image 80 for purchase shown in FIG. 15, theplayer C selects a desired purchase quantity from among selection itemsin a pull-down menu by operating a menu button 81, and then selects apurchase button 82. The purchase quantity included in the selectionitems are set so that the player C owns more items than that the playerB has already bid for. In the present embodiment, for example, when theplayer C owns none of the “item X”s, the number (zero) of “item X”sowned by the player C is three less than the number (three) the player Bhas already bid for. Therefore, the number that is equal to or more than“4” is displayed in the selection items of the menu button 81 (thenumbers “1” to “3” are not displayed).

Moreover, when the player C would like to acquire the “item X” of theplayer B, an operating image 80 for purchase similar to that of FIG. 15is also displayed on terminal display unit 24 (the image of “item A”instead of “item X” is displayed). That is, for example, when the playerC owns none of the “item A”s, the number (zero) of “item A”s owned bythe player C is three less than the number (three) the player A haslisted. Therefore, the number that is equal to or more than “4” isdisplayed in the selection items of the menu button 81 (the numbers “1”to “3” are not displayed).

In this way, the player C can purchase the “item X” and bid for the“item A” of the player A without taking time and effort only byselecting a purchase quantity in the operating image 80 for purchase.Similarly, the player C can purchase the “item A” and bid for the “itemX” of the player B without taking time and effort only by selecting apurchase quantity in the operating image 80 for purchase.

Other Embodiments

The present embodiment is for facilitating understanding of the presentinvention and does not intend to limit the interpretation of the presentinvention. Variations and modifications may be made in accordance withthe spirit and scope of the present invention and equivalents thereofare included in the present invention. In particular, embodimentsdescribed below are to be included in the present invention.

<Operating Image for Sellers>

In the aforementioned present embodiment, when the control unit 11judges that the player owns items the number of which is equal to ormore than a predetermined number by referring to the owned iteminformation stored in the storage unit 12, the control unit 11 may allowthe image generation unit 114 to generate an operating image for sellersincluding an indication that encourages the player to list the aboveitem. This makes it possible to actively exchange the item that hasbecome unnecessary.

<Operating Image for Bidders>

In the aforementioned present embodiment, by storing past tradeinformation that is information of the trades which have ever beencompleted, as a history in the storage unit 12, the control unit 11 mayallow the image generation unit 114 to generate an operating image forbidders including a list of past trades based on the history. Also, inthe operating image 60 for bidders, the appropriate number of items thatmatch the market price based on the history information may be presentedto the player. Thereby, the probability of completing a trade can beincreased.

<Server Device>

The present embodiment has described the game system 1 including oneserver device 10 as an example. However, the present invention is notlimited in this way. A plurality of server devices may be connected viaa network, and each server device may execute various types ofdistributed processing.

1-6. (canceled)
 7. A non-transitory computer-readable storage mediumwith a game program stored thereon, the game program instructing acomputer having a processor and a memory to execute the followingprocesses: a process to store in a storage unit trade informationrelated to a trade for exchanging an item in an exchange source for anitem in an exchange target, and player information in which each ofitems owned by players is associated with each of the players; aprocess, when a manipulated input performed by a player who accepts toexchange the item in the exchange target based on the trade is received,to judge whether or not the player owns the item in the exchange targetbased on the player information; and a process to generate data of agame screen for purchase for allowing the player to purchase the item inthe exchange target in a case where it is judged that the player doesnot own the item in the exchange target, the trade information includingan exchange amount that is associated with each of the items in theexchange source and each of the items in the exchange target, the playerinformation including the number of items that is associated with eachof the items owned by the players, the game program further instructingthe computer to execute, a process, when a manipulated input performedby a player who accepts to exchange the item in the exchange targetbased on the trade is received, to judge whether or not the number ofthe items in the exchange target owned by the player is more than theexchange amount of the items in the exchange target based on the playerinformation and the trade information; and a process to generate data ofa game screen for purchase for allowing the player to purchase thenumber of the items in the exchange target required to be added in acase where it is judged that the number of the items in the exchangetarget owned by the player is less than the exchange amount of the itemsin the exchange target.
 8. A non-transitory computer-readable storagemedium according to claim 7, wherein in a case where it is judged thatthe player owns the item in the exchange target, the game programinstructs the computer to execute a process to update the playerinformation so that the item in the exchange source becomes the item tobe owned by the player and the item in the exchange target becomes theitem not to be owned by the player.
 9. A non-transitorycomputer-readable storage medium according to claim 7, wherein whenallowing the player to input the number of the items in the exchangetarget to be purchased, the game screen for purchase is configured sothat only numbers that are greater than or equal to the number of itemsrequired to be added can be selected.
 10. A non-transitorycomputer-readable storage medium according to claim 7, wherein in a casewhere it is judged that the number of the items in the exchange targetowned by the player is more than the exchange amount of the items in theexchange target, the game program instructs the computer to execute aprocess to update the player information so that the items in theexchange source of the exchange amount become the items to be owned bythe player, and the items in the exchange target of the exchange amountbecome the items not to be owned by the player.
 11. An informationprocessing device comprising: a storage unit that stores tradeinformation related to a trade for exchanging an item in an exchangesource for an item in an exchange target, and player information inwhich each of items owned by players is associated with each of theplayers; a judging unit, when a manipulated input performed by a playerwho accepts to exchange the item in the exchange target based on thetrade is received, that judges whether or not the player owns the itemin the exchange target based on the player information; and a screendata generation unit, in a case where it is judged that the player doesnot own the item in the exchange target, that generates data of a gamescreen for purchase for allowing the player to purchase the item in theexchange target, wherein the trade information includes an exchangeamount that is associated with each of the items in the exchange sourceand each of the items in the exchange target, the player informationincludes the number of items that is associated with each of the itemsowned by the players, when a manipulated input performed by a player whoaccepts to exchange the item in the exchange target based on the tradeis received, the judging unit judges whether or not the number of theitems in the exchange target owned by the player is more than theexchange amount of the items in the exchange target based on the playerinformation and the trade information, and in a case where it is judgedthat the number of the items in the exchange target owned by the playeris less than the exchange amount of the items in the exchange target,the screen data generation unit generates data of a game screen forpurchase for allowing the player to purchase the number of the items inthe exchange target required to be added.